Clinical observation of allergic conjunctival diseases with portable and recordable slit-lamp device

Background: The incidence of allergic conjunctival diseases (ACDs) is gradually increasing worldwide. Both ophthalmologists and non-ophthalmologists prescribe eye drops to treat ACDs; however, there are many cases which are treated without sufficient examination and diagnosis of the eyes. We have invented a portable, recordable, and smartphone-attachable slit-lamp device—Smart Eye Camera (SEC). The purpose of this study was to compare the diagnostic abilities of ACDs between the SEC and the conventional, non-portable slit-lamp microscope. Methods: This prospective observational study included 32 eyes of 17 Japanese patients (mean age: 21.5 ± 14.8 years; range: 11–51 years; female: 5). The severity of 10 objective signs in the palpebral conjunctiva, bulbar conjunctiva, limbus, and cornea were scored on a grading scale of 0 to 4 (0 = normal; 1+ = mild; 2+ = moderate; 3+ = severe), respectively. First, the conventional slit-lamp microscope was used to examine the grade of the ACDs. Second, another ophthalmologist filmed the eyes using the SEC and two other ophthalmologists evaluated the grades on another day. The correlation and inter-rater reproducibility in total scores among the two devices were determined. Results: Total scores of clinical signs, evaluated by the two approaches, correlated significantly (both eyes: r = 0.918 (95% CI: 0.839 to 0.959; p < 0.001)), with substantial inter-rater agreement (weighted κ value = 0.631 (95% CI: 0.601 to 0.661; p < 0.001)). Conclusions: The SEC is as reliable as the conventional non-portable slit-lamp microscope for assessing ACDs.